期刊文献+
共找到3篇文章
< 1 >
每页显示 20 50 100
琼脂凝胶中形成铬酸铅周期性沉淀的机理研究 被引量:1
1
作者 张文敏 董吉溪 熊言林 《物理化学学报》 SCIE CAS CSCD 北大核心 1995年第5期390-394,共5页
选择硝酸铅和铬酸钾作为相互扩散的反应物以形成铬酸铅在琼脂凝胶中的周期性沉淀.分别在光照和黑暗中对六种不同浓度的硝酸铅溶液进行了实验.根据实验现象对周期性沉淀的形成提出了可能的机理.认为光辐射可使铬酸铅部分电离,从而减... 选择硝酸铅和铬酸钾作为相互扩散的反应物以形成铬酸铅在琼脂凝胶中的周期性沉淀.分别在光照和黑暗中对六种不同浓度的硝酸铅溶液进行了实验.根据实验现象对周期性沉淀的形成提出了可能的机理.认为光辐射可使铬酸铅部分电离,从而减慢了胶核成长速率,有利于汇聚成带. 展开更多
关键词 周期性沉淀 铬酸铅 琼脂凝胶 机理
下载PDF
Physicochemical Stages of Evolution: Ring-Like Structures in the Universe
2
作者 Georgi P. Gladyshev 《Natural Science》 2015年第5期266-269,共4页
This short digest is devoted to the mechanism of ring formation during the origination and evolution of planetary and satellite systems in the Universe. The appearance of these structures can be traced back to the phe... This short digest is devoted to the mechanism of ring formation during the origination and evolution of planetary and satellite systems in the Universe. The appearance of these structures can be traced back to the phenomenon of spatially periodic condensation which can be observed on the Earth. The author actually posited the existence of exoplanetary systems and the cosmic scale of this phenomenon. It was accurately predicted that Uranus, Neptune and other heavenly bodies have rings. The suggested general mechanism rationalized the Titius-Bode law which, while not being a precise law, often accurately describes the tendency towards varying distances between planets (and their moons) and central bodies. The possibility of this law manifestation in exoplanetary systems had been predicted by the author long before their discovery. Many exoplanetary systems have been discovered by now and there is some evidence corroborating the mechanism of spatially periodic condensation involved in the formation of ring-like structures in these systems. The author’s hypothesis is now becoming a theory or a fact. It appears that we are now witnessing the dawn of a new extensive cosmology, taking into account general physicochemical mechanisms of space object formation. 展开更多
关键词 Cosmology EVOLUTION Exoplanetary Systems liesegang phenomenon Solar System Titius-Bode Law
下载PDF
Transition of Liesegang Precipitation Systems: Simulations with an Adaptive Grid PDE Method
3
作者 Paul A.Zegeling Istvan Lagzi Ferenc Izsak 《Communications in Computational Physics》 SCIE 2011年第9期867-881,共15页
The dynamics of the Liesegang type pattern formation is investigated in a centrally symmetric two-dimensional setup.According to the observations in real experiments,the qualitative change of the dynamics is exhibited... The dynamics of the Liesegang type pattern formation is investigated in a centrally symmetric two-dimensional setup.According to the observations in real experiments,the qualitative change of the dynamics is exhibited for slightly different initial conditions.Two kinds of chemical mechanisms are studied;in both cases the pattern formation is described using a phase separation model including the CahnHilliard equations.For the numerical simulations we make use of an adaptive grid PDE method,which successfully deals with the computationally critical cases such as steep gradients in the concentration distribution and investigation of long time behavior.The numerical simulations show a good agreement with the real experiments. 展开更多
关键词 liesegang phenomenon numerical simulations adaptive grid technique
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部